MySQL Innodb如何找出阻塞事務之定位問題

#查詢 正在執行的事務：

select * from information_schema.innodb_trx;
#檢視正在鎖的事務
select * from information_schema.innodb_locks; 
#檢視等待鎖的事務
select * from information_schema.innodb_lock_waits;

show engine innodb status;

select * from performance_schema.threads where processlist_id=1227425559;

select * from performance_schema.threads where processlist_id=60178157;
select * from performance_schema.events_statememnts_current where thread_id =1227425559;

#檢視某段時間以來未關閉事務

select
trx_id,
trx_started,
trx_mysql_thread_id
from
information_schema.innodb_trx
where
trx_started < date_sub(now(), interval 1 minute)
and trx_operation_state is null
and trx_query is null;
select * from information_schema.innodb_lock_waits;
#檢視未關閉的事務：
select
a.trx_id,
a.trx_state,
a.trx_started,
a.trx_query,
b.id,
b. user,
b. host,
b.db,
b.command,
b.time,
b.state,
b.info
from
information_schema.innodb_trx a
left join information_schema.processlist b on a.trx_mysql_thread_id = b.id
where
b.command = 'sleep';

select b.trx_mysql_thread_id             as 'blocked_thread_id'

,b.trx_query                      as 'blocked_sql_text'
,c.trx_mysql_thread_id             as 'blocker_thread_id'
,c.trx_query                       as 'blocker_sql_text'
,( unix_timestamp() - unix_timestamp(c.trx_started) )
as 'blocked_time'
from   information_schema.innodb_lock_waits  a
inner join information_schema.innodb_trx b
on a.requesting_trx_id = b.trx_id
inner join information_schema.innodb_trx c
on a.blocking_trx_id = c.trx_id
where  ( unix_timestamp() - unix_timestamp(c.trx_started) ) > 4;
select a.sql_text,
c.id,
d.trx_started
from   performance_schema.events_statements_current a
join performance_schema.threads b
on a.thread_id = b.thread_id
join information_schema.processlist c
on b.processlist_id = c.id
join information_schema.innodb_trx d
on c.id = d.trx_mysql_thread_id
where c.id=17
order  by d.trx_started;

unknown table 'innodb_lock_waits' in information_schema

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